Abstract: This invention relates to the use of polycarbonate for the production of an optical recording medium in which secure high speed operation, a transcriptability of the pit/groove structure of >85% and sufficient disc flatness can be achieved and the polycarbonate is based on bisphenol A and the polycarbonate contains a release agent in an amount less than 2000 ppm.

Abstract: Emulsifier-free antifoams are obtainable by mixing a) from 80 to 99% by weight of at least one finely divided, virtually water-insoluble, inert solid with b) from 1 to 20% by weight of at least one hydrophobic, organic compound which has an antifoam action and is solid at room temperature in the absence of a solvent in a shear gradient such that the particle size of the compounds (b) which have an antifoam action is reduced to a mean particle size of from 0.5 to 15 ?m, emulsifier-free oil-in-water dispersions of mixtures of (a) and (b) are prepared by mixing the component (a) in an amount of from 80 to 99% by weight with the compounds of component (b) in an amount of from 1 to 20% by weight in the absence of emulsifiers in an extruder or kneader in a manner such that the mean particle size of the component (b) in the mixture is brought to 0.5 to 15 ?m, at up to 100° C.

Abstract: Antifoams and/or deaerators based on oil-in-water dispersions, whose oil phase contains at least one compound from the group consisting of the alcohols of at least 12 carbon atoms, alkoxylated fatty alcohols, mono-, di- and triglycerides of fatty acids, fatty acid esters of carboxylic acids of at least 12 carbon atoms and monohydric to tetrahydric alcohols of 1 to 24 carbon atoms, hydrocarbons having a boiling point above 200° C.